Repairs to Unlined RCP, Reaches IV-A and IV-B within Prado Inundation Pool

Value: $10,979,505 Contractor: Mladen Buntich Construction Designer: RBF Consulting Schedule: May 2011 – December 2012

Approximately six miles of the Brine Line (Reach IVA and IVB) is located within the Prado Dam inundation area. This portion of the Brine line was installed in the 1980’s and was constructed of unlined reinforced concrete pipe (RCP.) Core samples and a subsequent condition assessment report concluded deterioration of the concrete within the pipe. It was recommended to rehabilitate this portion of the Brine Line with a segmental slip-liner pipe designed to specifically meet the loading conditions imposed by the operation of Prado Dam. The Project as designed will eliminate the effect of the on-going structural deterioration of the unlined RCP, reduce the risk of a catastrophic failure in the environmentally sensitive Prado Basin and provide structural support to meet the loading conditions imposed by the operation of Prado Dam. The project will extend the useful life of these portions of the Brine Line an additional 50 years. Slip-lining is a process where a new pipe is pushed (segmental) into an existing pipe and grouting the annular space between the new pipe and old deteriorating pipe (host) pipe. Access to the existing pipe is through cutting and removing the top half of the existing pipe to allow sufficient space to add new segments of pipe that are pushed into place.